Optically active tolan derivatives

ABSTRACT

Novel optically active tolan derivative represented by the general formula (I) and process for preparing thereof; ##STR1## (wherein all the symbols are the same as defined in the appended claims) are disclosed. These are effective for use in preparation of liquid crystal material capable of effectively preventing the formation of the cross-talk phenomenon due to changes due to temperature in the high level multiplexing driving system.

This is a continuation of application Ser. No. 061,242 filed Jun. 15,1987 now U.S. Pat. No. 4,814,516, 3/21/84.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to novel optically active tolan derivatives whichare useful as electrooptical display materials.

2. Description of Prior Art

In recent years, liquid crystal display cells of high multiplexingdriving systems have been gradually increased in size, leading to anincreasing demand as displays for computer terminals, TV sets and soforth. With this increase in demand, liquid crystal materials havinghigh level multiplexibility have been more needed.

High level multiplexing driving systems are depending on change in theenvironmental temperature and the cross-talk phenomenon will easilyoccur. In order to prevent the formation of the cross-talk phenomenondue to changes in the environmental temperature, the following have beenknown; (1) a method in which a temperature compensation circuit isprovide in the liquid crystal display equipment, and (2) a method inwhich the temperature dependency of threshold voltage of liquid crystalmaterial is decreased by adding a chiral substance the molecularorientation of which is twisted right and a chiral substance themolecular orientation of which is twisted left, with respect to theliquid crystal material. The method (1), however, has a disadvantage inthat the equipment becomes expensive. Also the method (2) has adisadvantage in that the amount of the substances added is limitedbecause if the amount of the substances added is increased, the responsetime is decreased, although the substances are necessary to add in largeamounts in order to sufficiently obtain the desired effect; thereforethe desired effect cannot be obtained sufficiently.

SUMMARY OF THE INVENTION

An object of this invention is to efficiently prevent the cross-talkphenomenon due to changes in the environmental temperature in high levelmultiplexing driving systems.

Another object of this invention is to provide novel tolan derivativeswhich when added to various practical nematic liquid crystalcompositions, are able to sufficiently decrease the temperaturedependency of threshold voltage of the compositions even in smallamounts.

It has been found that the objects can be attained by using compoundsrepresented by the general formula (I) as described hereinafter.

This invention provides novel optically active tolan derivativesrepresented by the general formula (I): ##STR2## (wherein R represents astraight alkyl group having 2 to 8 carbon atoms, R' represents astraight alkyl group having 1 to 20 carbon atoms or a straight alkoxygroup having 1 to 20 carbon atoms, n represents 0 or 1, ##STR3##represents a trans(equatorial-equatorial) cyclohexyl ring, and Crepresents an asymmetrical carbon atom).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing the temperature dependency of thresholdvoltage of a chiral nematic liquid crystal composition which is preparedby adding 0.14 wt % of Optically Active Compound No. 33 (dextrorotation:) of the present invention to a mixed liquid crystal (A)commonly used as a nematic liquid crystal material at the present time.

FIG. 2 is a graph showing the temperature dependency of thresholdvoltage of a chiral nematic liquid crystal composition which is preparedby adding 0.70 wt % of Optically Active Compound No. 299 (dextrorotation) of this invention to a mixed liquid crystal (B) commonly usedas a nematic liquid crystal material at the present time.

DETAILED DESCRIPTION OF THE INVENTION

The compounds of the general formula (I) can be prepared according tothe following sequence. ##STR4## (wherein R, R', n and C are as definedabove).

4-iodophenyl-1'-methylalkyl ether is reacted with4-alkylphenylacetylene, 4-alkoxyphenylacetylene,4-(trans-4'-alkylcyclohexyl)phenylacetylene or4-(trans-4'-alkoxycyclohexyl)phenylacetylene in a solvent such asdiethylamine by the use of a catalyst such asbis(triphenylphosphine)palladium (II) chloride to form the compound ofthe general formula (I).

Representative examples of the compounds represented by the generalformula (I) are shown in Tables 1 and 2.

                  TABLE 1                                                         ______________________________________                                         ##STR5##                                                                     No.          R         R'                                                     ______________________________________                                        1            C.sub.2 H.sub.5                                                                         CH.sub.3                                               2            n-C.sub.3 H.sub.7                                                                       CH.sub.3                                               3            n-C.sub.4 H.sub.9                                                                       CH.sub.3                                               4            n-C.sub.5 H.sub.11                                                                      CH.sub.3                                               5            n-C.sub.6 H.sub.13                                                                      CH.sub.3                                               6            n-C.sub.7 H.sub.15                                                                      CH.sub.3                                               7            n-C.sub.8 H.sub.17                                                                      CH.sub.3                                               8            C.sub.2 H.sub.5                                                                         C.sub.2 H.sub.5                                        9            n-C.sub.3 H.sub.7                                                                       C.sub.2 H.sub.5                                        10           n-C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                        11           n-C.sub.5 H.sub.11                                                                      C.sub.2 H.sub.5                                        12           n-C.sub.6 H.sub.13                                                                      C.sub.2 H.sub.5                                        13           n-C.sub.7 H.sub.15                                                                      C.sub.2 H.sub.5                                        14           n-C.sub.8 H.sub.17                                                                      C.sub.2 H.sub.5                                        15           C.sub.2 H.sub.5                                                                         n-C.sub.3 H.sub.7                                      16           n-C.sub.3 H.sub.7                                                                       n-C.sub.3 H.sub.7                                      17           n-C.sub.4 H.sub.9                                                                       n-C.sub.3 H.sub.7                                      18           n-C.sub.5 H.sub.11                                                                      n-C.sub.3 H.sub.7                                      19           n-C.sub.6 H.sub.13                                                                      n-C.sub.3 H.sub.7                                      20           n-C.sub.7 H.sub.15                                                                      n-C.sub.3 H.sub.7                                      21           n-C.sub.8 H.sub.17                                                                      n-C.sub.3 H.sub.7                                      22           C.sub.2 H.sub.5                                                                         n-C.sub.4 H.sub.9                                      23           n-C.sub.3 H.sub.7                                                                       n-C.sub.4 H.sub.9                                      24           n-C.sub.4 H.sub.9                                                                       n-C.sub.4 H.sub.9                                      25           n-C.sub.5 H.sub.11                                                                      n-C.sub.4 H.sub.9                                      26           n-C.sub.6 H.sub.13                                                                      n-C.sub.4 H.sub.9                                      27           n-C.sub.7 H.sub.15                                                                      n-C.sub.4 H.sub.9                                      28           n-C.sub.8 H.sub.17                                                                      n-C.sub.4 H.sub.9                                      29           C.sub.2 H.sub.5                                                                         n-C.sub.5 H.sub.11                                     30           n-C.sub.3 H.sub.7                                                                       n-C.sub.5 H.sub.11                                     31           n-C.sub.4 H.sub.9                                                                       n-C.sub.5 H.sub.11                                     32           n-C.sub.5 H.sub.11                                                                      n-C.sub.5 H.sub.11                                     33           n-C.sub.6 H.sub.13                                                                      n-C.sub.5 H.sub.11                                     34           n-C.sub.7 H.sub.15                                                                      n-C.sub.5 H.sub.11                                     35           n-C.sub.8 H.sub.17                                                                      n-C.sub.5 H.sub.11                                     36           C.sub.2 H.sub.5                                                                         n-C.sub.6 H.sub.13                                     37           n-C.sub.3 H.sub.7                                                                       n-C.sub.6 H.sub.13                                     38           n-C.sub.4 H.sub.9                                                                       n-C.sub.6 H.sub.13                                     39           n-C.sub.5 H.sub.11                                                                      n-C.sub.6 H.sub.13                                     40           n-C.sub.6 H.sub.13                                                                      n-C.sub.6 H.sub.13                                     41           n-C.sub.7 H.sub.15                                                                      n-C.sub.6 H.sub.13                                     42           n-C.sub.8 H.sub.17                                                                      n-C.sub.6 H.sub.13                                     43           C.sub.2 H.sub.5                                                                         n-C.sub.7 H.sub.15                                     44           n-C.sub.3 H.sub.7                                                                       n-C.sub.7 H.sub.15                                     45           n-C.sub.4 H.sub.9                                                                       n-C.sub.7 H.sub.15                                     46           n-C.sub.5 H.sub.11                                                                      n-C.sub.7 H.sub.15                                     47           n-C.sub.6 H.sub.13                                                                      n-C.sub.7 H.sub.15                                     48           n-C.sub.7 H.sub.15                                                                      n-C.sub.7 H.sub.15                                     49           n-C.sub.8 H.sub.17                                                                      n-C.sub.7 H.sub.15                                     50           C.sub.2 H.sub.5                                                                         n-C.sub.8 H.sub.17                                     51           n-C.sub.3 H.sub.7                                                                       n-C.sub. 8 H.sub.17                                    52           n-C.sub.4 H.sub.9                                                                       n-C.sub.8 H.sub.17                                     53           n-C.sub.5 H.sub.11                                                                      n-C.sub.8 H.sub.17                                     54           n-C.sub.6 H.sub.13                                                                      n-C.sub.8 H.sub.17                                     55           n-C.sub.7 H.sub.15                                                                      n-C.sub.8 H.sub.17                                     56           n-C.sub.8 H.sub.17                                                                      n-C.sub.8 H.sub.17                                     57           C.sub.2 H.sub.5                                                                         n-C.sub.9 H.sub.19                                     58           n-C.sub.3 H.sub.7                                                                       n-C.sub.9 H.sub.19                                     59           n-C.sub.4 H.sub.9                                                                       n-C.sub.9 H.sub.19                                     60           n-C.sub.5 H.sub.11                                                                      n-C.sub.9 H.sub.19                                     61           n-C.sub.6 H.sub.13                                                                      n-C.sub.9 H.sub.19                                     62           n-C.sub.7 H.sub.15                                                                      n-C.sub.9 H.sub.19                                     63           n-C.sub.8 H.sub.17                                                                      n-C.sub.9 H.sub.19                                     64           C.sub.2 H.sub.5                                                                         n-C.sub.10 H.sub.21                                    65           n-C.sub.3 H.sub.7                                                                       n-C.sub.10 H.sub.21                                    66           n-C.sub.4 H.sub.9                                                                       n-C.sub.10 H.sub.21                                    67           n-C.sub.5 H.sub.11                                                                      n-C.sub.10 H.sub.21                                    68           n-C.sub.6 H.sub.13                                                                      n-C.sub.10 H.sub.21                                    69           n-C.sub.7 H.sub.15                                                                      n-C.sub.10 H.sub. 21                                   70           n-C.sub.8 H.sub.17                                                                      n-C.sub.10 H.sub.21                                    71           C.sub.2 H.sub.5                                                                         n-C.sub.11 H.sub.23                                    72           n-C.sub.3 H.sub.7                                                                       n-C.sub.11 H.sub.23                                    73           n-C.sub.4 H.sub.9                                                                       n-C.sub.11 H.sub.23                                    74           n-C.sub.5 H.sub.11                                                                      n-C.sub.11 H.sub.23                                    75           n-C.sub.6 H.sub.13                                                                      n-C.sub.11 H.sub.23                                    76           n-C.sub.7 H.sub.15                                                                      n-C.sub.11 H.sub.23                                    77           n-C.sub.8 H.sub.17                                                                      n-C.sub.11 H.sub.23                                    78           C.sub.2 H.sub.5                                                                         n-C.sub.12 H.sub.25                                    79           n-C.sub.3 H.sub.7                                                                       n-C.sub.12 H.sub.25                                    80           n-C.sub.4 H.sub.9                                                                       n-C.sub.12 H.sub.25                                    81           n-C.sub.5 H.sub.11                                                                      n-C.sub.12 H.sub.25                                    82           n-C.sub.6 H.sub.13                                                                      n-C.sub.12 H.sub.25                                    83           n-C.sub.7 H.sub.15                                                                      n-C.sub.12 H.sub.25                                    84           n-C.sub.8 H.sub.17                                                                      n-C.sub.12 H.sub.25                                    85           C.sub.2 H.sub.5                                                                         n-C.sub.13 H.sub.27                                    86           n-C.sub.3 H.sub.7                                                                       n-C.sub.13 H.sub.27                                    87           n-C.sub.4 H.sub.9                                                                       n-C.sub.13 H.sub.27                                    88           n-C.sub.5 H.sub.11                                                                      n-C.sub.13 H.sub.27                                    89           n-C.sub.6 H.sub.13                                                                      n-C.sub.13 H.sub.27                                    90           n-C.sub.7 H.sub.15                                                                      n-C.sub.13 H.sub.27                                    91           n-C.sub.8 H.sub.17                                                                      n-C.sub.13 H.sub.17                                    92           C.sub.2 H.sub.5                                                                         n-C.sub.14 H.sub.29                                    93           n-C.sub.3 H.sub.7                                                                       n-C.sub.14 H.sub.29                                    94           n-C.sub.4 H.sub.9                                                                       n-C.sub.14 H.sub.29                                    95           n-C.sub.5 H.sub.11                                                                      n-C.sub.14 H.sub.29                                    96           n-C.sub.6 H.sub.13                                                                      n-C.sub.14 H.sub.29                                    97           n-C.sub.7 H.sub.15                                                                      n-C.sub.14 H.sub.29                                    98           n-C.sub.8 H.sub.17                                                                      n-C.sub.14 H.sub.29                                    99           C.sub.2 H.sub.5                                                                         n-C.sub.15 H.sub.31                                    100          n-C.sub.3 H.sub.7                                                                       n-C.sub.15 H.sub.31                                    101          n-C.sub.4 H.sub.9                                                                       n-C.sub.15 H.sub.31                                    102          n-C.sub.5 H.sub.11                                                                      n-C.sub.15 H.sub.31                                    103          n-C.sub.6 H.sub.13                                                                      n-C.sub.15 H.sub.31                                    104          n-C.sub.7 H.sub.15                                                                      n-C.sub.15 H.sub.31                                    105          n-C.sub.8 H.sub.17                                                                      n-C.sub.15 H.sub.31                                    106          C.sub. 2 H.sub.5                                                                        n-C.sub.16 H.sub.33                                    107          n-C.sub.3 H.sub.7                                                                       n-C.sub.16 H.sub.33                                    108          n-C.sub.4 H.sub.9                                                                       n-C.sub.16 H.sub.33                                    109          n-C.sub.5 H.sub.11                                                                      n-C.sub.16 H.sub.33                                    110          n-C.sub.6 H.sub.13                                                                      n-C.sub.16 H.sub.33                                    111          n-C.sub.7 H.sub.15                                                                      n-C.sub.16 H.sub.33                                    112          n-C.sub.8 H.sub.17                                                                      n-C.sub.16 H.sub.33                                    113          C.sub.2 H.sub.5                                                                         n-C.sub.17 H.sub.35                                    114          n-C.sub.3 H.sub.7                                                                       n-C.sub.17 H.sub.35                                    115          n-C.sub.4 H.sub.9                                                                       n-C.sub.17 H.sub.35                                    116          n-C.sub.5 H.sub.11                                                                      n-C.sub.17 H.sub.35                                    117          n-C.sub.6 H.sub.13                                                                      n-C.sub.17 H.sub.35                                    118          n-C.sub.7 H.sub.15                                                                      n-C.sub.17 H.sub.35                                    119          n-C.sub.8 H.sub.17                                                                      n-C.sub.17 H.sub.35                                    120          C.sub.2 H.sub.5                                                                         n-C.sub.18 H.sub.37                                    121          n-C.sub.3 H.sub.7                                                                       n-C.sub.18 H.sub.37                                    122          n-C.sub.4 H.sub.9                                                                       n-C.sub.18 H.sub.37                                    123          n-C.sub.5 H.sub.11                                                                      n-C.sub.18 H.sub.37                                    124          n-C.sub.6 H.sub.13                                                                      n-C.sub.18 H.sub.37                                    125          n-C.sub.7 H.sub.15                                                                      n-C.sub.18 H.sub.37                                    126          n-C.sub.8 H.sub.17                                                                      n-C.sub.18 H.sub.37                                    127          C.sub.2 H.sub.5                                                                         n-C.sub.19 H.sub.39                                    128          n-C.sub.3 H.sub.7                                                                       n-C.sub.19 H.sub.39                                    129          n-C.sub.4 H.sub.9                                                                       n-C.sub.19 H.sub.39                                    130          n-C.sub.5 H.sub.11                                                                      n-C.sub.19 H.sub.39                                    131          n-C.sub.6 H.sub.13                                                                      n-C.sub.19 H.sub.39                                    132          n-C.sub.7 H.sub.15                                                                      n-C.sub.19 H.sub.39                                    133          n-C.sub.8 H.sub.17                                                                      n-C.sub.19 H.sub.39                                    134          C.sub.2 H.sub.5                                                                         n-C.sub.20 H.sub.41                                    135          n-C.sub.3 H.sub.7                                                                       n-C.sub.20 H.sub.41                                    136          n-C.sub.4 H.sub.9                                                                       n-C.sub.20 H.sub.41                                    137          n-C.sub.5 H.sub.11                                                                      n-C.sub.20 H.sub.41                                    138          n-C.sub.6 H.sub.13                                                                      n-C.sub.20 H.sub.41                                    139          n-C.sub.7 H.sub.15                                                                      n-C.sub.20 H.sub.41                                    140          n-C.sub.8 H.sub.17                                                                      n-C.sub.20 H.sub.41                                    141          C.sub.2 H.sub.5                                                                         CH.sub.3 O                                             142          n-C.sub.3 H.sub.7                                                                       CH.sub.3 O                                             143          n-C.sub.4 H.sub.9                                                                       CH.sub.3 O                                             144          n-C.sub.5 H.sub.11                                                                      CH.sub.3 O                                             145          n-C.sub.6 H.sub.13                                                                      CH.sub.3 O                                             146          n-C.sub.7 H.sub.15                                                                      CH.sub.3 O                                             147          n-C.sub.8 H.sub.17                                                                      CH.sub.3 O                                             148          C.sub.2 H.sub.5                                                                         C.sub.2 H.sub.5 O                                      149          n-C.sub.3 H.sub.7                                                                       C.sub.2 H.sub.5 O                                      150          n-C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5 O                                      151          n-C.sub.5 H.sub.11                                                                      C.sub.2 H.sub.5 O                                      152          n-C.sub.6 H.sub.13                                                                      C.sub.2 H.sub.5 O                                      153          n-C.sub.7 H.sub.15                                                                      C.sub.2 H.sub.5 O                                      154          n-C.sub.8 H.sub.17                                                                      C.sub.2 H.sub.5 O                                      155          C.sub.2 H.sub.5                                                                         n-C.sub.3 H.sub.7 O                                    156          n-C.sub.3 H.sub.7                                                                       n-C.sub.3 H.sub.7 O                                    157          n-C.sub.4 H.sub.9                                                                       n-C.sub.3 H.sub.7 O                                    158          n-C.sub.5 H.sub.11                                                                      n-C.sub.3 H.sub.7 O                                    159          n-C.sub.6 H.sub.13                                                                      n-C.sub.3 H.sub.7 O                                    160          n-C.sub.7 H.sub. 15                                                                     n-C.sub.3 H.sub.7 O                                    161          n-C.sub.8 H.sub.17                                                                      n-C.sub.3 H.sub.7 O                                    162          C.sub.2 H.sub.5                                                                         n-C.sub.4 H.sub.9 O                                    163          n-C.sub.3 H.sub.7                                                                       n-C.sub.4 H.sub.9 O                                    164          n-C.sub.4 H.sub.9                                                                       n-C.sub.4 H.sub.9 O                                    165          n-C.sub.5 H.sub.11                                                                      n-C.sub.4 H.sub.9 O                                    166          n-C.sub.6 H.sub.13                                                                      n-C.sub.4 H.sub.9 O                                    167          n-C.sub.7 H.sub.15                                                                      n-C.sub.4 H.sub.9 O                                    168          n-C.sub.8 H.sub.17                                                                      n-C.sub.4 H.sub.9 O                                    169          C.sub.2 H.sub.5                                                                         n-C.sub.5 H.sub.11 O                                   170          n-C.sub.3 H.sub.7                                                                       n-C.sub.5 H.sub.11 O                                   171          n-C.sub.4 H.sub.9                                                                       n-C.sub.5 H.sub.11 O                                   172          n-C.sub.5 H.sub.11                                                                      n-C.sub.5 H.sub.11 O                                   173          n-C.sub.6 H.sub.13                                                                      n-C.sub.5 H.sub.11 O                                   174          n-C.sub.7 H.sub.15                                                                      n-C.sub.5 H.sub.11 O                                   175          n-C.sub.8 H.sub.17                                                                      n-C.sub.5 H.sub.11 O                                   176          C.sub.2 H.sub.5                                                                         n-C.sub.6 H.sub.13 O                                   177          n-C.sub.3 H.sub.7                                                                       n-C.sub.6 H.sub.13 O                                   178          n-C.sub.4 H.sub.9                                                                       n-C.sub.6 H.sub.13 O                                   179          n-C.sub.5 H.sub.11                                                                      n-C.sub.6 H.sub.13 O                                   180          n-C.sub.6 H.sub.13                                                                      n-C.sub.6 H.sub.13 O                                   181          n-C.sub.7 H.sub.15                                                                      n-C.sub.6 H.sub.13 O                                   182          n-C.sub.8 H.sub.17                                                                      n-C.sub.6 H.sub.13 O                                   183          C.sub.2 H.sub.5                                                                         n-C.sub.7 H.sub.15 O                                   184          n-C.sub.3 H.sub.7                                                                       n-C.sub.7 H.sub.15 O                                   185          n-C.sub.4 H.sub.9                                                                       n-C.sub.7 H.sub.15 O                                   186          n-C.sub.5 H.sub.11                                                                      n-C.sub.7 H.sub.15 O                                   187          n-C.sub.6 H.sub.13                                                                      n-C.sub.7 H.sub.15 O                                   188          n-C.sub.7 H.sub.15                                                                      n-C.sub.7 H.sub.15 O                                   189          n-C.sub.8 H.sub.17                                                                      n-C.sub.7 H.sub.15 O                                   190          C.sub.2 H.sub.5                                                                         n-C.sub.8 H.sub.17 O                                   191          n-C.sub.3 H.sub.7                                                                       n-C.sub.8 H.sub.17 O                                   192          n-C.sub.4 H.sub.9                                                                       n-C.sub.8 H.sub.17 O                                   193          n-C.sub.5 H.sub.11                                                                      n-C.sub.8 H.sub.17 O                                   194          n-C.sub.6 H.sub.13                                                                      n-C.sub.8 H.sub.17 O                                   195          n-C.sub.7 H.sub.15                                                                      n-C.sub.8 H.sub.17 O                                   196          n-C.sub.8 H.sub.17                                                                      n-C.sub.8 H.sub.17 O                                   197          C.sub.2 H.sub.5                                                                         n-C.sub.9 H.sub.19 O                                   198          n-C.sub.3 H.sub.7                                                                       n-C.sub.9 H.sub.19 O                                   199          n-C.sub.4 H.sub.9                                                                       n-C.sub.9 H.sub.19 O                                   200          n-C.sub.5 H.sub.11                                                                      n-C.sub.9 H.sub.19 O                                   201          n-C.sub.6 H.sub.13                                                                      n-C.sub.9 H.sub.19 O                                   202          n-C.sub.7 H.sub.15                                                                      n-C.sub.9 H.sub.19 O                                   203          n-C.sub.8 H.sub.17                                                                      n-C.sub.9 H.sub.19 O                                   204          C.sub.2 H.sub.5                                                                         n-C.sub.10 H.sub.21 O                                  205          n-C.sub.3 H.sub.7                                                                       n-C.sub.10 H.sub.21 O                                  206          n-C.sub.4 H.sub.9                                                                       n-C.sub.10 H.sub.21 O                                  207          n-C.sub.5 H.sub.11                                                                      n-C.sub.10 H.sub.21 O                                  208          n-C.sub.6 H.sub.13                                                                      n-C.sub.10 H.sub.21 O                                  209          n-C.sub.7 H.sub.15                                                                      n-C.sub.10 H.sub.21 O                                  210          n-C.sub.8 H.sub. 17                                                                     n-C.sub.10 H.sub.21 O                                  211          C.sub.2 H.sub.5                                                                         n-C.sub.11 H.sub.23 O                                  212          n-C.sub.3 H.sub.7                                                                       n-C.sub.11 H.sub.23 O                                  213          n-C.sub.4 H.sub.9                                                                       n-C.sub.11 H.sub.23 O                                  214          n-C.sub.5 H.sub.11                                                                      n-C.sub.11 H.sub.23 O                                  215          n-C.sub.6 H.sub.13                                                                      n-C.sub.11 H.sub.23 O                                  216          n-C.sub.7 H.sub.15                                                                      n-C.sub.11 H.sub.23 O                                  217          n-C.sub.8 H.sub.17                                                                      n-C.sub.11 H.sub.23 O                                  218          C.sub.2 H.sub.5                                                                         n-C.sub.12 H.sub.25 O                                  219          n-C.sub.3 H.sub.7                                                                       n-C.sub.12 H.sub.25 O                                  220          n-C.sub.4 H.sub.9                                                                       n-C.sub.12 H.sub.25 O                                  221          n-C.sub.5 H.sub.11                                                                      n-C.sub.12 H.sub.25 O                                  222          n-C.sub.6 H.sub.13                                                                      n-C.sub.12 H.sub.25 O                                  223          n-C.sub.7 H.sub.15                                                                      n-C.sub.12 H.sub.25 O                                  224          n-C.sub.8 H.sub.17                                                                      n-C.sub.12 H.sub.25 O                                  225          C.sub.2 H.sub.5                                                                         n-C.sub.13 H.sub.27 O                                  226          n-C.sub.3 H.sub.7                                                                       n-C.sub.13 H.sub.27 O                                  227          n-C.sub.4 H.sub.9                                                                       n-C.sub.13 H.sub.27 O                                  228          n-C.sub.5 H.sub.11                                                                      n-C.sub.13 H.sub.27 O                                  229          n-C.sub.6 H.sub.13                                                                      n-C.sub.13 H.sub.27 O                                  230          n-C.sub.7 H.sub.15                                                                      n-C.sub.13 H.sub.27 O                                  231          n-C.sub.8 H.sub.17                                                                      n-C.sub.13 H.sub.27 O                                  232          C.sub.2 H.sub.5                                                                         n-C.sub.14 H.sub.29 O                                  233          n-C.sub.3 H.sub.7                                                                       n-C.sub.14 H.sub.29 O                                  234          n-C.sub.4 H.sub.9                                                                       n-C.sub.14 H.sub.29 O                                  235          n-C.sub.5 H.sub.11                                                                      n-C.sub.14 H.sub.29 O                                  236          n-C.sub.6 H.sub.13                                                                      n-C.sub.14 H.sub.29 O                                  237          n-C.sub.7 H.sub.15                                                                      n-C.sub.14 H.sub.29 O                                  238          n-C.sub.8 H.sub.17                                                                      n-C.sub.14 H.sub.29 O                                  239          C.sub.2 H.sub.5                                                                         n-C.sub.15 H.sub.31 O                                  240          n-C.sub.3 H.sub.7                                                                       n-C.sub.15 H.sub.31 O                                  241          n-C.sub.4 H.sub.9                                                                       n-C.sub.15 H.sub.31 O                                  242          n-C.sub.5 H.sub.11                                                                      n-C.sub.15 H.sub.31 O                                  243          n-C.sub.6 H.sub.13                                                                      n-C.sub.15 H.sub.31 O                                  244          n-C.sub.7 H.sub.15                                                                      n-C.sub.15 H.sub.31 O                                  245          n-C.sub.8 H.sub.17                                                                      n-C.sub.15 H.sub.31 O                                  246          C.sub.2 H.sub.5                                                                         n-C.sub.16 H.sub.33 O                                  247          n-C.sub.3 H.sub.7                                                                       n-C.sub.16 H.sub.33 O                                  248          n-C.sub.4 H.sub.9                                                                       n-C.sub.16 H.sub.33 O                                  249          n-C.sub.5 H.sub.11                                                                      n-C.sub.16 H.sub.33 O                                  250          n-C.sub.6 H.sub.13                                                                      n-C.sub.16 H.sub.33 O                                  251          n-C.sub.7 H.sub.15                                                                      n-C.sub.16 H.sub.33 O                                  252          n-C.sub.8 H.sub.17                                                                      n-C.sub.16 H.sub.33 O                                  253          C.sub.2 H.sub.5                                                                         n-C.sub.17 H.sub.35 O                                  254          n-C.sub.3 H.sub.7                                                                       n-C.sub.17 H.sub.35 O                                  255          n-C.sub.4 H.sub.9                                                                       n-C.sub.17 H.sub.35 O                                  256          n-C.sub.5 H.sub.11                                                                      n-C.sub.17 H.sub.35 O                                  257          n-C.sub.6 H.sub.13                                                                      n-C.sub.17 H.sub.35 O                                  258          n-C.sub.7 H.sub.15                                                                      n-C.sub.17 H.sub.35 O                                  259          n-C.sub.8 H.sub.17                                                                      n-C.sub.17 H.sub.35 O                                  260          C.sub.2 H.sub. 5                                                                        n-C.sub.18 H.sub.37 O                                  261          n-C.sub.3 H.sub.7                                                                       n-C.sub.18 H.sub.37 O                                  262          n-C.sub.4 H.sub.9                                                                       n-C.sub.18 H.sub.37 O                                  263          n-C.sub.5 H.sub.11                                                                      n-C.sub.18 H.sub.37 O                                  264          n-C.sub.6 H.sub.13                                                                      n-C.sub.18 H.sub.37 O                                  265          n-C.sub.7 H.sub.15                                                                      n-C.sub.18 H.sub.37 O                                  266          n-C.sub.8 H.sub.17                                                                      n-C.sub.18 H.sub.37 O                                  267          C.sub.2 H.sub.5                                                                         n-C.sub.19 H.sub.39 O                                  268          n-C.sub.3 H.sub.7                                                                       n-C.sub.19 H.sub.39 O                                  269          n-C.sub.4 H.sub.9                                                                       n-C.sub.19 H.sub.39 O                                  270          n-C.sub.5 H.sub.11                                                                      n-C.sub.19 H.sub.39 O                                  271          n-C.sub.6 H.sub.13                                                                      n-C.sub.19 H.sub.39 O                                  272          n-C.sub.7 H.sub.15                                                                      n-C.sub.19 H.sub.39 O                                  273          n-C.sub.8 H.sub.17                                                                      n-C.sub.19 H.sub.39 O                                  274          C.sub.2 H.sub.5                                                                         n-C.sub.20 H.sub.41 O                                  275          n-C.sub.3 H.sub.7                                                                       n-C.sub.20 H.sub.41 O                                  276          n-C.sub.4 H.sub.9                                                                       n-C.sub.20 H.sub.41 O                                  277          n-C.sub.5 H.sub.11                                                                      n-C.sub.20 H.sub.41 O                                  278          n-C.sub.6 H.sub.13                                                                      n-C.sub.20 H.sub.41 O                                  279          n-C.sub.7 H.sub.15                                                                      n-C.sub.20 H.sub.41 O                                  280          n-C.sub.8 H.sub.17                                                                      n-C.sub.20 H.sub.41 O                                  ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                         ##STR6##                                                                     No.          R            R'                                                  ______________________________________                                        281          C.sub.2 H.sub.5                                                                            CH.sub.3                                            282          n-C.sub.3 H.sub.7                                                                          CH.sub.3                                            283          n-C.sub.4 H.sub.9                                                                          CH.sub.3                                            284          n-C.sub.5 H.sub.11                                                                         CH.sub.3                                            285          n-C.sub.6 H.sub.13                                                                         CH.sub.3                                            286          n-C.sub.7 H.sub.15                                                                         CH.sub.3                                            287          n-C.sub.8 H.sub.17                                                                         CH.sub.3                                            288          C.sub.2 H.sub.5                                                                            C.sub.2 H.sub.5                                     289          n-C.sub.3 H.sub.7                                                                          C.sub.2 H.sub.5                                     290          n-C.sub.4 H.sub.9                                                                          C.sub.2 H.sub.5                                     291          n-C.sub.5 H.sub.11                                                                         C.sub.2 H.sub.5                                     292          n-C.sub.6 H.sub.13                                                                         C.sub.2 H.sub.5                                     293          n-C.sub.7 H.sub.15                                                                         C.sub.2 H.sub.5                                     294          n-C.sub.8 H.sub.17                                                                         C.sub.2 H.sub.5                                     295          C.sub.2 H.sub.5                                                                            n-C.sub.3 H.sub.7                                   296          n-C.sub.3 H.sub.7                                                                          n-C.sub.3 H.sub.7                                   297          n-C.sub.4 H.sub.9                                                                          n-C.sub.3 H.sub.7                                   298          n-C.sub.5 H.sub.11                                                                         n-C.sub.3 H.sub.7                                   299          n-C.sub.6 H.sub.13                                                                         n-C.sub.3 H.sub.7                                   300          n-C.sub.7 H.sub.15                                                                         n-C.sub.3 H.sub.7                                   301          n-C.sub.8 H.sub.17                                                                         n-C.sub.3 H.sub.7                                   302          C.sub.2 H.sub.5                                                                            n-C.sub.4 H.sub.9                                   303          n-C.sub.3 H.sub.7                                                                          n-C.sub.4 H.sub.9                                   304          n-C.sub.4 H.sub.9                                                                          n-C.sub.4 H.sub.9                                   305          n-C.sub.5 H.sub.11                                                                         n-C.sub.4 H.sub.9                                   306          n-C.sub.6 H.sub.13                                                                         n-C.sub.4 H.sub.9                                   307          n-C.sub.7 H.sub.15                                                                         n-C.sub.4 H.sub.9                                   308          n-C.sub.8 H.sub.17                                                                         n-C.sub.4 H.sub.9                                   309          C.sub.2 H.sub.5                                                                            n-C.sub.5 H.sub.11                                  310          n-C.sub.3 H.sub.7                                                                          n-C.sub.5 H.sub.11                                  311          n-C.sub.4 H.sub.9                                                                          n-C.sub.5 H.sub.11                                  312          n-C.sub.5 H.sub.11                                                                         n-C.sub.5 H.sub.11                                  313          n-C.sub.6 H.sub.13                                                                         n-C.sub.5 H.sub.11                                  314          n-C.sub.7 H.sub.15                                                                         n-C.sub.5 H.sub.11                                  315          n-C.sub.8 H.sub.17                                                                         n-C.sub.5 H.sub.11                                  316          C.sub.2 H.sub.5                                                                            n-C.sub.6 H.sub.13                                  317          n-C.sub.3 H.sub.7                                                                          n-C.sub.6 H.sub.13                                  318          n-C.sub.4 H.sub.9                                                                          n-C.sub.6 H.sub.13                                  319          n-C.sub.5 H.sub.11                                                                         n-C.sub.6 H.sub.13                                  320          n-C.sub.6 H.sub.13                                                                         n-C.sub.6 H.sub.13                                  321          n-C.sub.7 H.sub.15                                                                         n-C.sub.6 H.sub.13                                  322          n-C.sub.8 H.sub.17                                                                         n-C.sub.6 H.sub.13                                  323          C.sub.2 H.sub.5                                                                            n-C.sub.7 H.sub.15                                  324          n-C.sub.3 H.sub.7                                                                          n-C.sub.7 H.sub.15                                  325          n-C.sub.4 H.sub.9                                                                          n-C.sub.7 H.sub.15                                  326          n-C.sub.5 H.sub.11                                                                         n-C.sub.7 H.sub.15                                  327          n-C.sub.6 H.sub.13                                                                         n-C.sub.7 H.sub.15                                  328          n-C.sub.7 H.sub.15                                                                         n-C.sub.7 H.sub.15                                  329          n-C.sub.8 H.sub.17                                                                         n-C.sub.7 H.sub.15                                  330          C.sub.2 H.sub.5                                                                            n-C.sub.8 H.sub.17                                  331          n-C.sub.3 H.sub.7                                                                          n-C.sub. 8 H.sub.17                                 332          n-C.sub.4 H.sub.9                                                                          n-C.sub.8 H.sub.17                                  333          n-C.sub.5 H.sub.11                                                                         n-C.sub.8 H.sub.17                                  334          n-C.sub.6 H.sub.13                                                                         n-C.sub.8 H.sub.17                                  335          n-C.sub.7 H.sub.15                                                                         n-C.sub.8 H.sub.17                                  336          n-C.sub.8 H.sub.17                                                                         n-C.sub.8 H.sub.17                                  337          C.sub.2 H.sub.5                                                                            n-C.sub.9 H.sub.19                                  338          n-C.sub.3 H.sub.7                                                                          n-C.sub.9 H.sub.19                                  339          n-C.sub.4 H.sub.9                                                                          n-C.sub.9 H.sub.19                                  340          n-C.sub.5 H.sub.11                                                                         n-C.sub.9 H.sub.19                                  341          n-C.sub.6 H.sub.13                                                                         n-C.sub.9 H.sub.19                                  342          n-C.sub.7 H.sub.15                                                                         n-C.sub.9 H.sub.19                                  343          n-C.sub.8 H.sub.17                                                                         n-C.sub.9 H.sub.19                                  344          C.sub.2 H.sub.5                                                                            n-C.sub.10 H.sub.21                                 345          n-C.sub.3 H.sub.7                                                                          n-C.sub.10 H.sub.21                                 346          n-C.sub.4 H.sub.9                                                                          n-C.sub.10 H.sub.21                                 347          n-C.sub.5 H.sub.11                                                                         n-C.sub.10 H.sub.21                                 348          n-C.sub.6 H.sub.13                                                                         n-C.sub.10 H.sub.21                                 349          n-C.sub.7 H.sub.15                                                                         n-C.sub.10 H.sub. 21                                350          n-C.sub.8 H.sub.17                                                                         n-C.sub.10 H.sub.21                                 351          C.sub.2 H.sub.5                                                                            n-C.sub.11 H.sub.23                                 352          n-C.sub.3 H.sub.7                                                                          n-C.sub.11 H.sub.23                                 353          n-C.sub.4 H.sub.9                                                                          n-C.sub.11 H.sub.23                                 354          n-C.sub.5 H.sub.11                                                                         n-C.sub.11 H.sub.23                                 355          n-C.sub.6 H.sub.13                                                                         n-C.sub.11 H.sub.23                                 356          n-C.sub.7 H.sub.15                                                                         n-C.sub.11 H.sub.23                                 357          n-C.sub.8 H.sub.17                                                                         n-C.sub.11 H.sub.23                                 358          C.sub.2 H.sub.5                                                                            n-C.sub.12 H.sub.25                                 359          n-C.sub.3 H.sub.7                                                                          n-C.sub.12 H.sub.25                                 360          n-C.sub.4 H.sub.9                                                                          n-C.sub.12 H.sub.25                                 361          n-C.sub.5 H.sub.11                                                                         n-C.sub.12 H.sub.25                                 362          n-C.sub.6 H.sub.13                                                                         n-C.sub.12 H.sub.25                                 363          n-C.sub.7 H.sub.15                                                                         n-C.sub.12 H.sub.25                                 364          n-C.sub.8 H.sub.17                                                                         n-C.sub.12 H.sub.25                                 365          C.sub.2 H.sub.5                                                                            n-C.sub.13 H.sub.27                                 366          n-C.sub.3 H.sub.7                                                                          n-C.sub.13 H.sub.27                                 367          n-C.sub.4 H.sub.9                                                                          n-C.sub.13 H.sub.27                                 368          n-C.sub.5 H.sub.11                                                                         n-C.sub.13 H.sub.27                                 369          n-C.sub.6 H.sub.13                                                                         n-C.sub.13 H.sub.27                                 370          n-C.sub.7 H.sub.15                                                                         n-C.sub.13 H.sub.27                                 371          n-C.sub.8 H.sub.17                                                                         n-C.sub.13 H.sub.27                                 372          C.sub.2 H.sub.5                                                                            n-C.sub.14 H.sub.29                                 373          n-C.sub.3 H.sub.7                                                                          n-C.sub.14 H.sub.29                                 374          n-C.sub.4 H.sub.9                                                                          n-C.sub.14 H.sub.29                                 375          n-C.sub.5 H.sub.11                                                                         n-C.sub.14 H.sub.29                                 376          n-C.sub.6 H.sub.13                                                                         n-C.sub.14 H.sub.29                                 377          n-C.sub.7 H.sub.15                                                                         n-C.sub.14 H.sub.29                                 378          n-C.sub.8 H.sub.17                                                                         n-C.sub.14 H.sub.29                                 379          C.sub.2 H.sub.5                                                                            n-C.sub.15 H.sub.31                                 380          n-C.sub.3 H.sub.7                                                                          n-C.sub.15 H.sub.31                                 381          n-C.sub.4 H.sub.9                                                                          n-C.sub.15 H.sub.31                                 382          n-C.sub.5 H.sub.11                                                                         n-C.sub.15 H.sub.31                                 383          n-C.sub.6 H.sub.13                                                                         n-C.sub.15 H.sub.31                                 384          n-C.sub.7 H.sub.15                                                                         n-C.sub.15 H.sub.31                                 385          n-C.sub.8 H.sub.17                                                                         n-C.sub.15 H.sub.31                                 386          C.sub. 2 H.sub.5                                                                           n-C.sub.16 H.sub.33                                 387          n-C.sub.3 H.sub.7                                                                          n-C.sub.16 H.sub.33                                 388          n-C.sub.4 H.sub.9                                                                          n-C.sub.16 H.sub.33                                 389          n-C.sub.5 H.sub.11                                                                         n-C.sub.16 H.sub.33                                 390          n-C.sub.6 H.sub.13                                                                         n-C.sub.16 H.sub.33                                 391          n-C.sub.7 H.sub.15                                                                         n-C.sub.16 H.sub.33                                 392          n-C.sub.8 H.sub.17                                                                         n-C.sub.16 H.sub.33                                 393          C.sub.2 H.sub.5                                                                            n-C.sub.17 H.sub.35                                 394          n-C.sub.3 H.sub.7                                                                          n-C.sub.17 H.sub.35                                 395          n-C.sub.4 H.sub.9                                                                          n-C.sub.17 H.sub.35                                 396          n-C.sub.5 H.sub.11                                                                         n-C.sub.17 H.sub.35                                 397          n-C.sub.6 H.sub.13                                                                         n-C.sub.17 H.sub.35                                 398          n-C.sub.7 H.sub.15                                                                         n-C.sub.17 H.sub.35                                 399          n-C.sub.8 H.sub.17                                                                         n-C.sub.17 H.sub.35                                 400          C.sub.2 H.sub.5                                                                            n-C.sub.18 H.sub.37                                 401          n-C.sub.3 H.sub.7                                                                          n-C.sub.18 H.sub.37                                 402          n-C.sub.4 H.sub.9                                                                          n-C.sub.18 H.sub.37                                 403          n-C.sub.5 H.sub.11                                                                         n-C.sub.18 H.sub.37                                 404          n-C.sub.6 H.sub. 13                                                                        n-C.sub.18 H.sub.37                                 405          n-C.sub.7 H.sub.15                                                                         n-C.sub.18 H.sub.37                                 406          n-C.sub.8 H.sub.17                                                                         n-C.sub.18 H.sub.37                                 407          C.sub.2 H.sub.5                                                                            n-C.sub.19 H.sub.39                                 408          n-C.sub.3 H.sub.7                                                                          n-C.sub.19 H.sub.39                                 409          n-C.sub.4 H.sub.9                                                                          n-C.sub.19 H.sub.39                                 410          n-C.sub.5 H.sub.11                                                                         n-C.sub.19 H.sub.39                                 411          n-C.sub.6 H.sub.13                                                                         n-C.sub.19 H.sub.39                                 412          n-C.sub.7 H.sub.15                                                                         n-C.sub.19 H.sub.39                                 413          n-C.sub.8 H.sub.17                                                                         n-C.sub.19 H.sub.39                                 414          C.sub.2 H.sub.5                                                                            n-C.sub.20 H.sub.41                                 415          n-C.sub.3 H.sub.7                                                                          n-C.sub.20 H.sub.41                                 416          n-C.sub.4 H.sub.9                                                                          n-C.sub.20 H.sub.41                                 417          n-C.sub.5 H.sub.11                                                                         n-C.sub.20 H.sub.41                                 418          n-C.sub.6 H.sub.13                                                                         n-C.sub.20 H.sub.41                                 419          n-C.sub.7 H.sub.15                                                                         n-C.sub.20 H.sub.41                                 420          n-C.sub.8 H.sub.17                                                                         n-C.sub.20 H.sub.41                                 421          C.sub.2 H.sub.5                                                                            CH.sub.3 O                                          422          n-C.sub.3 H.sub.7                                                                          CH.sub. 3 O                                         423          n-C.sub.4 H.sub.9                                                                          CH.sub.3 O                                          424          n-C.sub.5 H.sub.11                                                                         CH.sub.3 O                                          425          n-C.sub.6 H.sub.13                                                                         CH.sub.3 O                                          426          n-C.sub.7 H.sub.15                                                                         CH.sub.3 O                                          427          n-C.sub.8 H.sub.17                                                                         CH.sub.3 O                                          428          C.sub.2 H.sub.5                                                                            C.sub.2 H.sub.5 O                                   429          n-C.sub.3 H.sub.7                                                                          C.sub.2 H.sub.5 O                                   430          n-C.sub.4 H.sub.9                                                                          C.sub.2 H.sub.5 O                                   431          n-C.sub.5 H.sub.11                                                                         C.sub.2 H.sub.5 O                                   432          n-C.sub.6 H.sub.13                                                                         C.sub.2 H.sub.5 O                                   433          n-C.sub.7 H.sub.15                                                                         C.sub.2 H.sub.5 O                                   434          n-C.sub.8 H.sub.17                                                                         C.sub.2 H.sub.5 O                                   435          C.sub.2 H.sub.5                                                                            n-C.sub.3 H.sub.7 O                                 436          n-C.sub.3 H.sub.7                                                                          n-C.sub.3 H.sub.7 O                                 437          n-C.sub.4 H.sub.9                                                                          n-C.sub.3 H.sub.7 O                                 438          n-C.sub.5 H.sub.11                                                                         n-C.sub.3 H.sub.7 O                                 439          n-C.sub.6 H.sub.13                                                                         n-C.sub.3 H.sub.7 O                                 440          n-C.sub.7 H.sub.15                                                                         n-C.sub.3 H.sub.7 O                                 441          n-C.sub.8 H.sub.17                                                                         n-C.sub.3 H.sub.7 O                                 442          C.sub.2 H.sub.5                                                                            n-C.sub.4 H.sub.9 O                                 443          n-C.sub.3 H.sub.7                                                                          n-C.sub.4 H.sub.9 O                                 444          n-C.sub.4 H.sub.9                                                                          n-C.sub.4 H.sub.9 O                                 445          n-C.sub.5 H.sub.11                                                                         n-C.sub.4 H.sub.9 O                                 446          n-C.sub.6 H.sub.13                                                                         n-C.sub.4 H.sub.9 O                                 447          n-C.sub.7 H.sub.15                                                                         n-C.sub.4 H.sub.9 O                                 448          n-C.sub.8 H.sub.17                                                                         n-C.sub.4 H.sub.9 O                                 449          C.sub.2 H.sub.5                                                                            n-C.sub.5 H.sub.11 O                                450          n-C.sub.3 H.sub.7                                                                          n-C.sub.5 H.sub.11 O                                451          n-C.sub.4 H.sub.9                                                                          n-C.sub.5 H.sub.11 O                                452          n-C.sub.5 H.sub.11                                                                         n-C.sub.5 H.sub.11 O                                453          n-C.sub.6 H.sub.13                                                                         n-C.sub.5 H.sub.11 O                                454          n-C.sub.7 H.sub.15                                                                         n-C.sub.5 H.sub.11 O                                455          n-C.sub.8 H.sub.17                                                                         n-C.sub.5 H.sub.11 O                                456          C.sub.2 H.sub.5                                                                            n-C.sub.6 H.sub.13 O                                457          n-C.sub.3 H.sub.7                                                                          n-C.sub.6 H.sub.13 O                                458          n-C.sub.4 H.sub.9                                                                          n-C.sub.6 H.sub.13 O                                459          n-C.sub.5 H.sub.11                                                                         n-C.sub.6 H.sub.13 O                                460          n-C.sub.6 H.sub.13                                                                         n-C.sub.6 H.sub.13 O                                461          n-C.sub.7 H.sub.15                                                                         n-C.sub.6 H.sub.13 O                                462          n-C.sub.8 H.sub.17                                                                         n-C.sub.6 H.sub.13 O                                463          C.sub.2 H.sub.5                                                                            n-C.sub.7 H.sub.15 O                                464          n-C.sub.3 H.sub.7                                                                          n-C.sub.7 H.sub.15 O                                465          n-C.sub.4 H.sub.9                                                                          n-C.sub.7 H.sub.15 O                                466          n-C.sub.5 H.sub.11                                                                         n-C.sub.7 H.sub.15 O                                467          n-C.sub.6 H.sub.13                                                                         n-C.sub.7 H.sub.15 O                                468          n-C.sub.7 H.sub.15                                                                         n-C.sub.7 H.sub.15 O                                469          n-C.sub.8 H.sub.17                                                                         n-C.sub.7 H.sub.15 O                                470          C.sub.2 H.sub.5                                                                            n-C.sub.8 H.sub.17 O                                471          n-C.sub.3 H.sub.7                                                                          n-C.sub.8 H.sub.17 O                                472          n-C.sub.4 H.sub.9                                                                          n-C.sub.8 H.sub.17 O                                473          n-C.sub.5 H.sub.11                                                                         n-C.sub. 8 H.sub.17 O                               474          n-C.sub.6 H.sub.13                                                                         n-C.sub.8 H.sub.17 O                                475          n-C.sub.7 H.sub.15                                                                         n-C.sub.8 H.sub.17 O                                476          n-C.sub.8 H.sub.17                                                                         n-C.sub.8 H.sub.17 O                                477          C.sub.2 H.sub.5                                                                            n-C.sub.9 H.sub.19 O                                478          n-C.sub.3 H.sub.7                                                                          n-C.sub.9 H.sub.19 O                                479          n-C.sub.4 H.sub.9                                                                          n-C.sub.9 H.sub.19 O                                480          n-C.sub.5 H.sub.11                                                                         n-C.sub.9 H.sub.19 O                                481          n-C.sub.6 H.sub.13                                                                         n-C.sub.9 H.sub.19 O                                482          n-C.sub.7 H.sub.15                                                                         n-C.sub.9 H.sub.19 O                                483          n-C.sub.8 H.sub.17                                                                         n-C.sub.9 H.sub.19 O                                484          C.sub.2 H.sub.5                                                                            n-C.sub.10 H.sub.21 O                               485          n-C.sub.3 H.sub.7                                                                          n-C.sub.10 H.sub.21 O                               486          n-C.sub.4 H.sub.9                                                                          n-C.sub.10 H.sub.21 O                               487          n-C.sub.5 H.sub.11                                                                         n-C.sub.10 H.sub.21 O                               488          n-C.sub.6 H.sub.13                                                                         n-C.sub.10 H.sub.21 O                               489          n-C.sub.7 H.sub.15                                                                         n-C.sub.10 H.sub.21 O                               490          n-C.sub.8 H.sub.17                                                                         n-C.sub.10 H.sub.21 O                               491          C.sub.2 H.sub.5                                                                            n-C.sub.11 H.sub.23 O                               492          n-C.sub.3 H.sub.7                                                                          n-C.sub.11 H.sub.23 O                               493          n-C.sub.4 H.sub.9                                                                          n-C.sub.11 H.sub.23 O                               494          n-C.sub.5 H.sub.11                                                                         n-C.sub.11 H.sub.23 O                               495          n-C.sub.6 H.sub.13                                                                         n-C.sub.11 H.sub.23 O                               496          n-C.sub.7 H.sub.15                                                                         n-C.sub.11 H.sub.23 O                               497          n-C.sub.8 H.sub.17                                                                         n-C.sub.11 H.sub.23 O                               498          C.sub.2 H.sub.5                                                                            n-C.sub.12 H.sub.25 O                               499          n-C.sub.3 H.sub.7                                                                          n-C.sub.12 H.sub.25 O                               500          n-C.sub.4 H.sub.9                                                                          n-C.sub.12 H.sub.25 O                               501          n-C.sub.5 H.sub.11                                                                         n-C.sub.12 H.sub.25 O                               502          n-C.sub.6 H.sub.13                                                                         n-C.sub.12 H.sub.25 O                               503          n-C.sub.7 H.sub.15                                                                         n-C.sub.12 H.sub.25 O                               504          n-C.sub.8 H.sub.17                                                                         n-C.sub.12 H.sub.25 O                               505          C.sub.2 H.sub.5                                                                            n-C.sub.13 H.sub.27 O                               506          n-C.sub.3 H.sub.7                                                                          n-C.sub.13 H.sub.27 O                               507          n-C.sub.4 H.sub.9                                                                          n-C.sub.13 H.sub.27 O                               508          n-C.sub.5 H.sub.11                                                                         n-C.sub.13 H.sub.27 O                               509          n-C.sub.6 H.sub.13                                                                         n-C.sub.13 H.sub.27 O                               510          n-C.sub.7 H.sub.15                                                                         n-C.sub.13 H.sub.27 O                               511          n-C.sub.8 H.sub.17                                                                         n-C.sub.13 H.sub.27 O                               512          C.sub.2 H.sub.5                                                                            n-C.sub.14 H.sub.29 O                               513          n-C.sub.3 H.sub.7                                                                          n-C.sub.14 H.sub.29 O                               514          n-C.sub.4 H.sub.9                                                                          n-C.sub.14 H.sub.29 O                               515          n-C.sub.5 H.sub.11                                                                         n-C.sub.14 H.sub.29 O                               516          n-C.sub.6 H.sub.13                                                                         n-C.sub.14 H.sub.29 O                               517          n-C.sub.7 H.sub.15                                                                         n-C.sub.14 H.sub.29 O                               518          n-C.sub.8 H.sub.17                                                                         n-C.sub.14 H.sub.29 O                               519          C.sub.2 H.sub.5                                                                            n-C.sub.15 H.sub.31 O                               520          n-C.sub.3 H.sub.7                                                                          n-C.sub.15 H.sub.31 O                               521          n-C.sub.4 H.sub.9                                                                          n-C.sub.15 H.sub.31 O                               522          n-C.sub.5 H.sub.11                                                                         n-C.sub.15 H.sub.31 O                               523          n-C.sub.6 H.sub.13                                                                         n-C.sub. 15 H.sub.31 O                              524          n-C.sub.7 H.sub.15                                                                         n-C.sub.15 H.sub.31 O                               525          n-C.sub.8 H.sub.17                                                                         n-C.sub.15 H.sub.31 O                               526          C.sub.2 H.sub.5                                                                            n-C.sub.16 H.sub.33 O                               527          n-C.sub.3 H.sub.7                                                                          n-C.sub.16 H.sub.33 O                               528          n-C.sub.4 H.sub.9                                                                          n-C.sub.16 H.sub.33 O                               529          n-C.sub.5 H.sub.11                                                                         n-C.sub.16 H.sub.33 O                               530          n-C.sub.6 H.sub.13                                                                         n-C.sub.16 H.sub.33 O                               531          n-C.sub.7 H.sub.15                                                                         n-C.sub.16 H.sub.33 O                               532          n-C.sub.8 H.sub.17                                                                         n-C.sub.16 H.sub.33 O                               533          C.sub.2 H.sub.5                                                                            n-C.sub.17 H.sub.35 O                               534          n-C.sub.3 H.sub.7                                                                          n-C.sub.17 H.sub.35 O                               535          n-C.sub.4 H.sub.9                                                                          n-C.sub.17 H.sub.35 O                               536          n-C.sub.5 H.sub.11                                                                         n-C.sub.17 H.sub.35 O                               537          n-C.sub.6 H.sub.13                                                                         n-C.sub.17 H.sub.35 O                               538          n-C.sub.7 H.sub.15                                                                         n-C.sub.17 H.sub.35 O                               539          n-C.sub.8 H.sub.17                                                                         n-C.sub.17 H.sub.35 O                               540          C.sub.2 H.sub.5                                                                            n-C.sub.18 H.sub.37 O                               541          n-C.sub.3 H.sub.7                                                                          n-C.sub.18 H.sub.37 O                               542          n-C.sub.4 H.sub.9                                                                          n-C.sub.18 H.sub.37 O                               543          n-C.sub.5 H.sub.11                                                                         n-C.sub.18 H.sub.37 O                               544          n-C.sub.6 H.sub.13                                                                         n-C.sub.18 H.sub.37 O                               545          n-C.sub.7 H.sub.15                                                                         n-C.sub.18 H.sub.37 O                               546          n-C.sub.8 H.sub.17                                                                         n-C.sub.18 H.sub.37 O                               547          C.sub.2 H.sub.5                                                                            n-C.sub.19 H.sub.39 O                               548          n-C.sub.3 H.sub.7                                                                          n-C.sub.19 H.sub.39 O                               549          n-C.sub.4 H.sub.9                                                                          n-C.sub.19 H.sub.39 O                               550          n-C.sub.5 H.sub.11                                                                         n-C.sub.19 H.sub.39 O                               551          n-C.sub.6 H.sub.13                                                                         n-C.sub.19 H.sub.39 O                               552          n-C.sub.7 H.sub.15                                                                         n-C.sub.19 H.sub.39 O                               553          n-C.sub.8 H.sub.17                                                                         n-C.sub.19 H.sub.39 O                               554          C.sub.2 H.sub.5                                                                            n-C.sub.20 H.sub.41 O                               555          n-C.sub.3 H.sub.7                                                                          n-C.sub.20 H.sub.41 O                               556          n-C.sub.4 H.sub.9                                                                          n-C.sub.20 H.sub.41 O                               557          n-C.sub.5 H.sub.11                                                                         n-C.sub.20 H.sub.41 O                               558          n-C.sub.6 H.sub.13                                                                         n-C.sub.20 H.sub.41 O                               559          n-C.sub.7 H.sub.15                                                                         n-C.sub.20 H.sub.41 O                               560          n-C.sub.8 H.sub.17                                                                         n-C.sub.20 H.sub.41 O                               ______________________________________                                    

In the general formula (I), the sum of the number of carbon atomscontained in the alkyl group represented by R and the number of carbonatoms contained in the alkyl or alkoxy group represented by R' ispreferably 3 to 20. Compounds of the general formula (I) wherein nrepresents O, R represents a straight alkyl group having 2 to 8 carbonatoms, and R' represents a straight alkyl group having 1 to 12 carbonatoms, or wherein n represents 0, R represents a straight alkyl grouphaving 2 to 8 carbon atoms, and R' represents a straight alkoxy grouphaving 1 to 12 are preferred. In addition, compounds of the generalformula (I) wherein n represents 1, R represents a straight alkyl grouphaving 2 to 8 carbon atoms, and R' represents a straight alkyl grouphaving 1 to 12 carbon atoms, or wherein n represents 1, R represents astraight alkyl group having 2 to 8 carbon atoms, and R' represents astraight alkoxy group having 1 to 12 carbon atoms are preferred.

Many nematic liquid crystal compositions commonly used at the presenttime can be sufficiently decreased in the temperature dependency ofthreshold voltage by adding the compounds of the general formula (I) ofthis invention only in small amounts.

FIG. 1 is a graph showing the temperature dependency of thresholdvoltage of each of a mixed liquid crystal (A) commonly used as a nematicliquid crystal material at the present time and of a chiral nematicliquid crystal composition as prepared by adding 0.14 wt % of CompoundNo. 33 (dextro rotation) of the present invention to the mixed liquidcrystal (A). This chiral nematic liquid crystal composition has a pitchof 200 μm.

The mixed liquid crystal (A) is composed of: ##STR7##

FIG. 2 is a graph showing the temperature dependency of thresholdvoltage of each of a mixed liquid crystal (B) commonly used as a nematicliquid crystal material and of a chiral nematic liquid crystalcomposition as prepared by adding 0.70 wt % of Compound No. 299 (dextrorotation) of the general formula (I) of the present invention to themixed liquid crystal (B). This chiral nematic liquid crystal compositionhas a pitch of 100 μm.

The mixed liquid crystal (B) is composed of: ##STR8##

It can be seen that the compounds of the general formula (I) have aneffect of decreasing the temperature dependency of threshold voltage ofa nematic liquid crystal composition when added thereto in a smallamount.

The present invention is described in greater detail with reference tothe following examples.

EXAMPLE 1

4.0 g (0.012 mol) of a compound having the formula (a): ##STR9##(wherein (S) indicates that the absolute arrangement with respect to achiral center is sinister, and (+) indicates dextro rotation) wasdissolved in 10 ml of diethylamine, and 24 mg (0.034 mmol) ofbis(triphenylphosphine)palladium (II) chloride and 60 mg (0.31 mmol) ofcopper (II) iodide were added thereto. To the resulting mixture wasdropped 2.1 g (0.012 mol) of p-n-pentylphenylacetylene while stirringthe mixture at room temperature. After the dropwise addition wascompleted, the mixture was stirred for about 7 hours at roomtemperature. After the completion of the reaction, the reaction mixturewas added to an excessive amount of hydro-chloric acid cooled with ice,and the resulting mixture was extracted with toluene and then washedwith water and dried, and further recrystallized from ethanol andpurified to obtain 3.4 g (0.0090 mol) of a compound having the followingformula: ##STR10##

Yield: 75%.

[α]_(D) ²⁵ =+3.7.

Transition Temperature: 38° C. (C→I).

The symbol "C" indicates a crystal phase, and "I", and isometric liquidphase.

EXAMPLE 2

The procedure of Example 1 was repeated with the exception that acompound having the formula (b): ##STR11## (wherein (R) indicates thatthe absolute arrangement with respect to a chiral center is rectus, and(-) indicates levo rotation) was used in place of the compound of theformula (a), to thereby obtain a compound having the following formula:##STR12##

Yield: 69%.

[α]_(D) ²⁵ =-2.4.

Transition temperature: 38° C. (C→I).

EXAMPLE 3

The procedure of Example 1 was repeated with the exception that 3.3 g(0.012 mol) of a compound having the formula: ##STR13## was used inplace of the compound of the formula (a), and 1.6 g (0.012 mol) ofp-methoxyphenylacetylene was used in place of thep-n-pentylphenylacetylene, to thereby obtain a compound having theformula: ##STR14##

Yield: 58%.

[α]_(D) ²⁵ =-21.0°.

Transition Temperature: 69° C. (C→I).

EXAMPLE 4

The procedure of Example 1 was repeated with the exception that 2.7 g(0.012 mol) of 4-(trans-4'-n-propylcyclohexyl)phenylacetylene was usedin place of the p-n-pentylphenylacetylene, to thereby a compound havingthe following formula: ##STR15##

Yield: 65%.

[α]_(D) ²⁵ =+1.80.

Transition Temperature: 75° C. (C→Ch), 117° C. (CH⃡I).

The symbol "C" indicates a crystal phase; "Ch", a colesteric phase; and"I", an isometric liquid phase.

The optically active compound of the present invention is a compoundcapable of decreasing the temperature dependency of threshold voltage ofa nematic liquid crystal composition commonly used at the present timewhen added thereto in a small amount. Thus the optically active compoundof the present invention is effective in preparation of liquid crystalmaterial which is capable of effectively preventing the formation of thecross-talk phenomenon due to changes in the environmental temperature inhigh level multiplexing driving system.

What is claimed is:
 1. In a nematic liquid crystal compositioncontaining an additive to decrease the temperature dependency ofthreshold voltage of the composition, the improvement wherein theadditive is an optically active tolan derivative represented by theformula, ##STR16## wherein R represents a straight chain alkyl grouphaving 2 to 8 carbon atoms, R¹ represents a straight chain alkoxy grouphaving 1 to 20 carbon atoms, and C* represents an asymmetrical carbon.2. The optically active tolan derivative as in claim 1, wherein R is C₂H₅ and R' is O--CH₃.